15. Special signs are used to precede numbers and capital letters. 16. The number sign is a cell with dots in positions 3, 4, 5, and 6. 17. The first ten letters of the alphabet represent numerals if they are preceded by the number sign. — 18. For example, a cell that would otherwise represent the letter a represents the Arabic numeral 1 if it is preceded by a number sign. 19. Similarly, whenever a cell with a single dot in position 6 appears, the reader knows that the next letter is a capital. 20. Braille can be written by manual or mechanical means. 21. A Braille writing machine is similar to a typewriter except that it has only six keys, one corresponding to each dot in the Braille cell. 22. An ordinary personal computer can convert printed material to Braille by using a special device that embosses dots on paper. 23. Another method of writing Braille involves using a slate and stylus to form raised dots on paper. 24. Although Braille provides visually impaired individuals with access to important information found in books, its usefulness doesn't stop there. copynight o mesaw-fil education. Permission is granted to reproduce for classroom use. — 25. Because writing is such an intrinsic part of everyday life, Braille's most important role may be furnishing visually impaired people with a medium for letters, grocery lists, and phone messages.